Interlock for sewing machines



Jan. 9, 1923.

A. GRIEB. INTERLOCK FOR SEWING MACHINES.

FILED APK.2I, I92].

INVENTOR %1! K TTORNE AT N ESSESZ ALFRED GRIEB, OJF ELIZABETH, NEW JERSEY, ASSIGNOR TO THE SINGER MANUFAC TUBING COMPANY, OF ELIZABETH, NEW JERSEY, ACORPORATION OF NEW JERSEY.

INTERLOCK FOR SEWING MACHINES.

Application filed April 21,

To all whom it may concern.

Be it known that I, Anrnnn Ginnn, a bitizen of the United States, residing at Eliza-- beth, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in interlocks for Sewing Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to sewing machines such as are customarily operated by power in factory installation and has for an object to provide a simplified and improved interlock for preventing the starting of the machine while the work-clamp, presser-foot or other manually operated part is displaced from sewing position, and to prevent accidental displacen'ient of such part from sewing position while the machine is running.

The invention is adapted, more particularly, for use on a machine having a stopmotion device of the well known type illustrated in the United States patent to Barron No. 1,093,241 of April 14, 1914. Such a stop-motion device comprises a Starting le ver which may be swung manually in one direction to start the machine and which swings automatically in the opposite direction to stop the machine at a predetermined time.

The invention comprises a stop which is shi-ftable into and out'of the path of movement of the stop-motion lever, and which is connected to be positioned within the range of starting movement of said lever when another manually controlled part of the machine, such for example-as the workclamp, is opened, or displaced from the position it should occupy during the sewing. -Preferably, the stop is in the form of a swinging element, pivoted on a horizontal axis in hearings on the bracket-arm standard or goose-neck of the machine.

In the accompanying drawings, Fig. 1 1s aside elevation of a sewing machine, embodying the invention. Fig. 2 'is a f1ag mentary horizontal section through the bracket-arm standard and Fig. 3 is a per-- spective view of the stop element.

In the preferred embodiment of the 111- -vention chosen for the purpose of the pres-- ent disclosure the invention isembodied in a label cutting, folding and stitching ma chine, the constructive features of which are more fully disclosed in my cope'ndmg apph- 1921. Serial No. 463,257.

cation Serial No. 416,927, filed Oct. 14-, 1920.

The frame of the machine comprises the bed 1, and the .usual bracket-arm including the standard 2 and horizontal member 3 terminating in the head at in which is journaled the reciprocating needle-bar 5 and presser-bar 6; the former carrying the needle 7.

Mounted to slide over-the bed 1 is the usual work-clamp including the lower supporting bar 8 and upper clamp-carryin arm 9 terminating in the head 10 in whic is mounted the spring-actuated slide-bar 11 carrying at its lower end the shiftable work engaging element or label-clamping foot 12. The presser-bar 6 carries at its lower end the usual bracket-piece 13 which extends under and is adapted to lift the lateral pin 14. carried by the slide-bar 11.

The front end of the work-clamp is moved in a rectangular path over the bed 1 by means of the usual connections with the pattern-wheel 15. which is geared to the main-shaft 16 carrying at its rearward end the tight and loose pulleys 17 and 18, respectively.

The running of the machine is controlled by the usual stop-motion device disclosed in said Patent No. 1,093,241 and comprising the stop-motion. lever 19, pivoted at 20 to the bracket 21 and carrying the belt shipper 22 and the stopping plunger 23 which cooperates with the stopping cam .24 to stop the machine when the lever 19 occupies full line position, Fig. 1.

When the lever 19 is shifted inwardly or toward the bracketarm,'Fig. 1, the belt is shifted onto thetight pulley 17 to start the machine; the lever 19 being retained in running position for a predetermined time by the spring-pressed latch 25 which engages the tooth 25' on the lever 19. The

tripping time of the latch 25 is governed by a lug 26 on the pattern-wheel 15. A

ed to receive a stop-screw 35 which is held 11c spring 27 forces the stop-motion lever to and toggle-link 38 so as to position the released r otherwise interfered with-{nor being shifted or. fed' to the machin V ter cannot be started until thework clamp; is closed and all parts have been return d" movement force thepusher 53 nut *36. Connected to the stop-arm 33 at 37 is one end of the toggle-link 38 the opposite end of which is connected at 39 to one arm 40 of a manually controlled three-armed lever pivoted at 41 to anupstanding bracket 42 mounted on the bed 1. Another arm 43 of the three-armed lever is connected by the link 44 to the depending arm 45 of a bellcrank-lever pivoted at 46 to a bracket 47 mounted on the bracket-arm 3. The horizontal arm 48 of the bell crank-lever extends beneath a collar 49 on the presser-bar 6 and em-- braces said presser-bar, whereby when a pull is exerted by the operator upon the chain 50 connected to thearm 40, the presser-bar and clamping foot 12 will be lifted to release the work. The spring 51 connected at its opposite ends tothe arms 40 and 45 tendsto restore the parts to their full line position, Fig. 1, when the pull on the chain 50 is relieved. The three-armed lever also includes a depending arm 52 which it the embodiment of the invention illustrated is adapted to oper ate a shiftable element in the form of a label feed slide or pusher 53' more fully disclosed in my said copending application.

It will be observedthatwhenthe clamp ing foot 12 has been lifted, or the pusher 53 advanced to dotted line position, Fig. 1,

the stop-arm 33 has necessarily been shifted by the straightening action of the. arm 10 stop-screw 35 directly in the path of inward movement 'of the-stop-motion lever 19. Consequently as long as the parts controlled by the manually operated arm 40 are out of sewing position OIQOCOHPYI dotted line position, Fig. l, inward movement of the lever 19 to start the machine is blocked-by the stop-screw 35 on'the stop-lever 33. On the other hand, when the machine is running, the stop-motion lever 19 is in'its inward position and acts through the stop-arm 33 and,

link 38 to block'the advance of the pusher 53 and to prevent the lifting of the clamping foot to release the work. 1 Thus, when the machine is running, the, work cannot be can any manually controlledpart to an unsafe position. When th' atto safe running positions.

stop-motion lever 19 is locked injs t opping', positlon. Accidental startingpr'ess ire upen said lever 19 willnot be transmittedIto-thel] cam and movable-to establish "and in- -.terrupt driving ,relationbetwee'n thepower toggle 38, 40 is broken,wheruponlinward of thestop-motion lever; 19 will,

rearwardly;f-and thejclamping foot lifting arm' sn wman-y,

work-clamp operating, connectionsijuntil;;the

ment of said starting and stopping lever and bracket-.arm,.rising therefrom,.stitch-form- It Wlll also beobservedf that w en 'the toggle 40 and link'38 are straightened,-

thereby forcibly vrestoring the parts to safe running positionsbefore the machine starts.

Having thus set forth thenature of the invention, what I claim herein is 1. A sewing machine having, in combination, stitch-forming mechanism, power means, a stop-motion device including a .stopping cam and a starting and stopping :control lever adaptedto cooperatively-engage said cam and movable to establish and interrupt driving relation between the power means and th stitch-forming mechanism, a shiftable element and connections for manually operating the same between sewing periods," and a stop movable into and out of the range of movement of said starting and stopping lever and connected to be positioned by the operating connections for said shiftable element, substantially as and for the purposes specified.

2. A sewing machine having, in combina tion, stitch-forming mechanism, power means, a stop-motion device including a stopping cam and a starting and stopping control lever adapted to cooperatively en gage. said cam and movable to establish and interrupt driving relation between the power means and the stitch-forming mechanism, a' shiftable element and connections for manu ally operating the. same between sewing periods, and a stop-arm pivoted to swing into and out of the range of movement of said starting and stopping lever and connected to be 'posltioned by the operating connections for said shiftable element, substantially as and for the purposes specified.

3. A sewing machine having, in combination, stitch-forming mechanism, power means, a stop-motion device including a stopping cam and a. starting and stopping control lever adapted to cooperatively engage said cam 'and'movable to establish and. interrupt driving relation between the power means and the stitch-forming mechanism, a shlftable element and connections'for manually operating the same between sewing pemods, and a stop-arm horizontally pivoted to swing into and out of the range of moveconnected, to .be

posltloned by the operating connections for said shiftable element, substantlally as and for the purposes specified. g 4. A sewlng machine having, in combination, a frameincluding a bed and a hollow in mechanismincorporated insaid frame, ower means a stop-motion device including a stoppmg-cam and a starting and stopping lever *adaptedto cooperatively engage means and the stitch-forming mechanism, a

:shiftable element and connections for manu- I ally operating the same between sewing pesaid bracket-arm and movable into and out of the range of movement of said starting:

and stopping lever and connected to be positioned by the operating connections for said shiftable element, substantially as and for the purposes specified.

5. A sewing machine having, in combination, stitch-forming mechanism, a starting and stopping device including a shiftable starting and stopping element for controlling the period of action of the stitch-for1ning mechanism, a work-engaging element and connectionsfor manually operating the same between sewing periods, a stop movable into and out of the range of move ment of said starting and stoping element in the direction'of movement of the latter and a toggle link connection between said stop and the connections for operating the work-engaging element.

6. A sewing machine having, in combination, stitch-forming mechanism, a frame including a bed and bracket-arm, power means, a stop-motion device including a stopping cam and a starting and stopping lever pivotally carried by the bracket-arm and shiftable out of engagement with said cam and toward the bracket arm to establish driving relation between the power means and the stitch-forming mechanism, a shiftable work-engaging element and connections for manually operating the samebetween sew-- ALFRED GRIEB. 

